Yacine KadiEngineering Department, CERN, Geneva, Switzerland

Department of Energy Science/WCU, SKKU, Seoul, KoreaEquinox summit: Energy 2030

Waterloo, Ontario, CanadaJune 4-9, 2011

Concerns Related to Conventional Nuclear Power Plants

� Accidents & Safety

� Nuclear Proliferation (North Korea)

� Accumulation of Radioactive Wastes

� Depletion of Uranium Resources

These problems need to be solved before extending further the use of nuclear power.

Required Conditions for Sustainable Nuclear Power

• Extremely high level of inherent safety

• Minimal production of long lived waste and elimination of the need of the geologic depositories

• High resistance to diversion• High resistance to diversion

• More efficient use of available natural fuel, without the need of isotopic enrichment

• Lower cost of the heat produced and higher operating temperature

Why are subWhy are sub--critical reactors sometimes called critical reactors sometimes called “green nuclear power”?“green nuclear power”?

Question 1

Could nuclear fission be exploited in a way that Could nuclear fission be exploited in a way that is acceptable to Society?is acceptable to Society?

Based on nuclear fission:Based on nuclear fission:• It is a subsub--criticalcritical system (no Chernobyl-

type accident possible) driven by a driven by a proton acceleratorproton accelerator;

• It is a fast neutronfast neutron system (use of lead as moderator/coolant);

Carlo Rubbia’s Energy Amplifier

• It is a fast neutronfast neutron system (use of lead as moderator/coolant);

• It is equipped with passive safety passive safety featuresfeatures (no core meltdown);

• It is using thorium based fuelthorium based fuel rather than uranium used in PWRs (minimize waste, proliferation resistant)

Question 2

Can you really have nuclear energy without Can you really have nuclear energy without uranium or plutonium?uranium or plutonium?

Thorium as fuel in a system breeding 233U

It is the presence of the accelerator which makes it possible to choose the optimum fuel.

Low equilibrium concentration of TRU makes the system favourable for their elimination:

Pu 10–4 in Th vs 12% in U.

1.1. Abundance of ResourcesAbundance of Resources� large reserves to sustain requirement for a few generations

2.2. Resource consumption is matched by resource productionResource consumption is matched by resource production� Neither breeding nor burning – just self-sustaining

3.3. Environmental friendlyEnvironmental friendly

Thorium as Sustainable Nuclear Energy Source for the Future

Thorium-based fuel 3.3. Environmental friendlyEnvironmental friendly� Low long lived radiotoxicity/transmutation nuclide

4.4. Waste SafetyWaste Safety� Fuel itself is a stable matrix for actinide and fission products, better than

vitrified glass

5.5. Proliferation resistanceProliferation resistance� U232 inherent presence in U233/difficult to reprocess

Thorium-based fuel

cycle fits the bill

Question 3

Why hasn’t thorium been used as aWhy hasn’t thorium been used as anuclear fuel before?nuclear fuel before?

Industrial Experience of Thorium Critical Reactors

Country Name Type Power Operation

Germany AVR HTGR 15 MWe 1967 - 1988

Germany THTR HTGR 300 MWe 1985 - 1989

UK, OECD-EURATOM also Norway, Sweden & Switzerland

Dragon HTGR 20 MWth 1966 -1973 Switzerland

USA Fort St Vrain HTGR 330 MWe 1976 – 1989

USA, ORNL MSRE MSBR 7.5 MWth 1964 – 1969

USAShippingport & Indian Point

LWBR PWR

100 MWe285 MWe

1977 – 19821962 – 1980

IndiaKAMINI, CIRUS & DHRUVA

MTR30 kWth40 MWth100 MWth

In operation

Most Project Using Thorium were Terminated by the 1980s

Main Reasons:• The thorium fuel cycle could not compete economically with

the well-known uranium cycle• Lack of political support for the development of nuclear

technology after the Chernobyl accidentLack of political support for the development of nuclear technology after the Chernobyl accident

• Increased worldwide concern regarding the proliferation risk associated with reprocessing of spent fuel

Except for India:Except for India:• That utilizes thorium for its long term energy security

Question 4

Has anyone built subHas anyone built sub--critical reactors?critical reactors?

Development is Time-Consuming

The FEAT Experiment

20

25

30

35

40

En

erg

y g

ain

Energy gain vs. kinetic energy�(Average from all counters & MonteCarlo)

G = ~ 30G0

(1 - k)

S. Andriamonje et al., Phys. Lett. B348 (1995) 697-709

3.6 tons of natural uranium3.6 tons of natural uranium

• Consistent measurement of the energy gain.• Validation of innovative MC simulation tool.• Energy gain increases with particle beam energy � constant above 900 MeV � modest requirement for

Energy Amplifier.• The first Energy Amplifier (with a power rating ≈ watt) was operated at CERN in 1994.

0

5

10

15

0 0.5 1 1.5 2 2.5 3 3.5Proton Kinetic Energy (GeV)

Avg. Measured Gain Monte Carlo Gain

G0 ~ 3�k ~ 0.9

Worldwide Programs

Project Neutron Source Core Purpose

FEAT(CERN)

Proton (0.6 to 2.75 GeV)

(~1010p/s)

Thermal (≈ 1 W)

Reactor physics of thermal subcritical system (k≈0.9) with spallation source - done

TARC(CERN)

Proton (0.6 to 2.75 GeV)

(~1010p/s)

Fast(≈ 1 W)

Lead slowing down spectrometry and transmutation of LLFP - done

MUSE (France)

DT (~1010n/s)Fast (< 1 kW)

Reactor physics of fast subcritical system - done

YALINA(Belorus)

DT (~1010n/s)Fast (< 1 kW)

Reactor physics of thermal & fast subcritical system - done

MEGAPIE Proton (600 Me)----- Demonstration of 1MW target for short period - done MEGAPIE

(Switzerland)

Proton (600 Me)

+ Pb-Bi (1MW)----- Demonstration of 1MW target for short period - done

TRADE (Italy)

Proton (140 MeV)

+ Ta (40 kW)

Thermal(200 kW)

Demonstration of ADS with thermal feedback - cancelled

TEF-P(Japan)

Proton (600 MeV)

+ Pb-Bi (10W, ~1012n/s)

Fast(< 1 kW)

Coupling of fast subcritical system with spallation source including MA fuelled configuration - postponed

SAD(Russia)

Proton (660 MeV)

+ Pb-Bi (1 kW)

Fast(20 kW)

Coupling of fast subcritical system with spallation source - cancelled

TEF-T(Japan)

Proton (600 MeV)

+ Pb-Bi (200 kW)-----

Dedicated facility for demonstration and accumulation of material data base for long term - postponed

MYRRHA(Belgium)

Proton (350 MeV)

+ Pb-Bi (1.5 MW)

Fast(60 MW)

Experimental ADS - under study FP6/FP7 EUROTRANS

Question 5

Can they really burn old nuclear waste to Can they really burn old nuclear waste to generate electricity?generate electricity?

Partitioning &Transmutation

• P/T applies to TRU (Pu and Minor Actinides) and Long Lived Fission Products.

• It should be kept in mind that • It should be kept in mind that Plutonium is a special case: it can be considered as a valuable resource or part of the wastes.

• However, P/T technologies apply to the most general case.

Question 6

Can Accelerator-Driven Systems meet a 10 GW

implementation scale within the next 20 years?

Layout of a 1500 MWth thorium-fuelled ADS

• A turning point ~2000: the objectives of GENERATION-IV do include P/T (waste minimization).

Deployment Scenario

20202020• Implementation of MA

partitioning• Waste minimization (Vitrified include P/T (waste minimization).

P/T is seen from now on, as consistent with sustainability and non-proliferation objectives: it is the path towards “Advanced Fuel Cycles”.

• Implementation: closely related to FR deployment decision.

• Waste minimization (Vitrified FP)

Deployment Scenario

232232ThTh

NuclearNuclear

wastewaste

232232Th+ Th+ 233233UU

ADSADS LWR → ADSLWR → ADS

wastewaste

STAGE 1STAGE 1 STAGE 2STAGE 2

Three Stage Programme of India

Thorium in the Centre StageThorium in the Centre Stage

SUMMARY

• Accelerator-driven systems have additional safety margins, which give operational flexibility to future systems for safe and clean energy production

Can atomic power be green?Can atomic power be green?

operational flexibility to future systems for safe and clean energy production and/or waste transmutation (including nuclear weapons)

• Present accelerator technology offers the possibility for applying a closed thorium cycle, but also for an open once-through ‘cycle’ using thorium oxide with some topping fuel and a very high fuel burn up. The Energy Amplifier is one of the examples with high potential

• Next step: DEMO? When? Where?

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Yacine KadiEngineering Department, CERN, Geneva, Switzerland

Department of Energy Science/WCU, SKKU, Seoul, Korea

Equinox summit: Energy 2030

Waterloo, Ontario, Canada

June 4-9, 2011

Thank youThank you

Yacine KadiYacine KadiEngineering Department, CERN, Geneva, SwitzerlandEngineering Department, CERN, Geneva, Switzerland

Department of Energy Science/WCU, SKKU, Seoul, KoreaDepartment of Energy Science/WCU, SKKU, Seoul, Korea